Not all people **** talk when they win. When Red Nails had enough people to premade, we did against Asylum and lost everytime. We learned from team play in losing, and this is to be expected. People will lost against organized teams, especially at first.
If a team thinks they will appear to be more "pro" by posting a screen shot let them. Don't let it take enjoyment out of the game for you. I would encourage everyone to do premades.